(Natural Factors) While known for its antioxidant and anti-aging abilities, E doesn’t stop there. The Cambridge Heart Antioxidant Study reported a 77% drop in non-fatal heart attacks when people took 400-800 IU of vitamin E per day. Experts agree that getting enough E from the diet is difficult. Natural Factors offers the d-alpha, d-beta, d-delta, and d-gamma forms that are absorbed 2x better than synthetic forms. 3 month supply.